E-mails, photographs and interviews paint a sordid mosaic of a "'Lord of the Flies' environment" at the Kabul-based camp in which private security guards from the firm ArmorGroup downed vodka, stripped naked and harassed the locals during raucous parties, according to a letter to Secretary of State Hillary Clinton from the nonprofit watchdog group Project on Government Oversight.

"These are very serious allegations and we are treating them that way," a state department spokesman said.

Clinton has "zero tolerance" for the behavior alleged by the watchdog group and ordered a "review of the whole system," the spokesman said.